1. Field of the Invention
The present invention relates generally to kiln fuel systems and, more specifically, to a method and apparatus for storing, conveying and igniting a fuel consisting substantially of bitumen and water within a kiln.
2. Description of the Prior Art
Numerous types of fuel delivery systems designed for kilns have been provided in the prior art. For example, U.S. Pat. Nos. 3,595,544; 4,234,106; 5,339,75 1; 5,806,442 and 5,837,052 all are illustrative of such prior art. While these units may be suitable for the particular purpose to which they address, they would not be as suitable for the purposes of the present invention as heretofore described.
This invention relates to the combination of a rotary kiln for sintering raw material into sinter having drive means connected to the rotary kiln for rotating the rotary kiln, heating means disposed adjacent one end of the rotary kiln for directing a heated fluid through the rotary kiln to sinter the raw material as the new raw material passes through the rotary kiln from the other end of the rotary kiln to the one end of the rotary kiln, and control means associated with the rotary kiln for controlling the operation of one of the drive means and the heating means.
A series of operatively interconnected fuel flow regulators are adapted to meter and direct the flow of particulate fuel from a fuel conveying system into the burners of a furnace or kiln. Each regulator is fed by a conveying system and includes a feeder housing having a flow metering impeller and feed rotor arrangement. Each housing includes an adjustable fuel orifice communicating with a respective burner.
A firing system is provided for charging a plurality of incoming combustible fuel modules containing a known amount of a parameter of interest into a heated zone of a rotating kiln. The firing system separates incoming fuel modules into a plurality of stages based on the parameter amount in each fuel module. The system then removes fuel modules from the plurality of stages in a selected order to maintain an average parameter amount for fuel modules charged into the kiln at substantially a preselected level. The system charges fuel modules into the kiln in the selected order. The system determines an optimum time to charge each fuel module into the rotating kiln to maintain an average amount of the parameter of interest supplied to the kiln substantially at the preselected level.
A feeding apparatus for feeding whole tires into a cement kiln comprising a feed opening in the shell of the kiln, a passageway including a sleeve extending within and outside the kiln, an arcuate sector valve device for closing the passageway and timed to open so as to allow the tires to fall into the kiln through the passageway. The sector valve having an outer perforated wall and an inner wall, the perforated wall allowing ambient air to circulate between the outer and inner wall to keep the outer wall cool for contact with the tires. A transfer device is provided for transferring the tires onto the feeding apparatus wherein the transfer device includes fingers while the feeding apparatus includes a fork receiving tray interdigitated with the fingers to pick up the tires as the kiln rotates.
Contaminated coal ash, for example flyash contaminated with carbon is introduced to hot clinker in a cooler downstream of a cement kiln; the carbon is combusted in the cooler to provide a cement clinker having an effective content of flyash free of carbon; this permits use of flyash contaminated with carbon without the need for separate special steps for carbon removal; volatile contaminants of contaminants having a volatile component, for example absorbed ammonia are similarly removed in the cooler by volatilization.
The present invention relates generally to kiln fuel systems and, more specifically, to a method and apparatus for storing, conveying and igniting a fuel consisting substantially of bitumen and water within a kiln.
A primary object of the present invention is to provide a kiln fuel system that will overcome the shortcomings of prior art devices.
A further object of the present invention is to provide a kiln fuel system which is able to use a mixture consisting substantially of bitumen and water as a kiln fuel as an economically viable substitute for conventionally used fuel oil.
Another object of the present invention is to provide a kiln fuel system having a bottom fill storage tank or tanks to eliminate foaming of the bitumen/water fuel mixture.
A yet further object of the present invention is to provide a kiln fuel system able to preheat the fuel to a desired selectable temperature.
A still further object of the present invention is to provide a kiln fuel system able to pressurize the fuel to a desired pressure for delivery.
An even further object of present invention is to provide a kiln fuel system able to heat the pressurized fuel to as desired selectable temperature.
Yet another object of the invention is to provide a kiln fuel system able to vary the length and shape of the flame produced within the kiln.
Yet another object of the present invention is to provide a kiln fuel system using a bitumen and water fuel having physical, chemical and combustion characteristics which have little impact on the final quality of the cement produced by a dry process.
Still yet another object of the present invention is to provide a kiln fuel system having emission characteristics below those required by International Environmental and Safety Regulations.
Another object of the present invention is to provide a kiln fuel system that is simple and easy to use.
A still further object of the present invention is to provide a kiln fuel system that is economical in cost to manufacture.
Additional objects of the present invention will appear as the description proceeds.
The bitumen/water fuel mixture of the present invention is stored at ambient temperature in bottom filled fuel tank. Alternatively, a plurality of bottom filled fuel tanks may be used. The fuel is extracted from the tank by a suction heater, the suction heater preheating the fuel using an indirect heat exchanger with thermal oil as the heat medium. The pre heating selectively raises the temperature of the fuel to substantially 40xc2x0 C. before carrying the fuel to a high pressure pump station. The high pressure pump station increases the fuel pressure to be atomized by the burner. After pressurizing, the fuel is fed via a conduit to a high pressure heater station. The temperature of the fuel is increased in the high pressure heater station to substantially 70xc2x0 C. by one or more indirect heat exchangers using thermal oil as the heat medium. The pressurized and heated fuel is fed through another conduit to the burner valve train in which it is filtered. The burner valve train is comprised of a plurality of pressure gauges, regulating valves, check valves, a quick shut off switch and mass flow meter for monitoring and adjusting the flame within the kiln.
The foregoing and other objects and advantages will appear from the description to follow. In the description reference is made to the accompanying drawing, which forms a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. In the accompanying drawing, like reference characters designate the same or similar parts throughout the several views.
The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims.
To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims.